ionization

Definition of ionization

1: the act or process of ionizing something : conversion of a substance into ions
Then other photons, collisions or an electric field cause ionization of the excited neutral species.— G. Samuel Hurst and Vladilen S. Letokhov

2: the state of being ionized
While the light flashes themselves are not harmful, the tissue ionization caused by the intruding particle near the end of its track is indeed deadly to some affected cells.— James D. Burke